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If your automobile runs out of fuel while you are driving the engine stops but you do not come to an abrupt stop. This concept that most explains why is
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INERTIA
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Whirl a rock at the end of a string on an ice-covered pond and it follows a circular path. If the string breaks, the tendency of the rock is to
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FOLLOW A STRAIGHT-LINE PATH
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A heavy object and a light object are dropped at the same time from rest in a vacuum. The heavier object reaches the ground
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AT THE SAME TIME AS THE LIGHTER OBJECT
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A sheet of paper can be withdrawn from under a container of milk without toppling it if the paper is jerked quickly. This best demonstrates that
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THE MILK CARTON HAS INERTIA
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The newton is a unit of
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FORCE
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An object is pulled northward by a force of 10N and at the same time another force of 5N pulls it southward. The magnitude of the resultant (net) force on the object is
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5 N
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The two measurements necessary for calculating average speed are:
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DISTANCE AND TIME
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A ball is thrown upwards and returns to the same position (neglecting air resistance). Compared with its original speed after release, its speed when it returns is about
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THE SAME
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The gain in speed each second for a freely-falling object is about
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10 M/S
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When a rock thrown straight upward gets to the exact top of its path, its
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VELOCITY IS ZERO AND ITS ACCELERATION IS ABOUT 10 METERS PER SECOND DOWN
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Acceleration is defined as the change in
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VELOCITY DIVIDED BY THE TIME INTERVAL
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Suppose you are in a car that is going around a curve. The speedometer reads a constant 30 kilometers per hour. These are true:
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YOU AND THE CAR ARE ACCELERATING-YOUR SPEED IS CONSTANT
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Your weight is:
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THE GRAVITATIONAL ATTRACTION FORCE BETWEEN YOU AND THE EARTH
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An object is propelled along a straight-line path in space by a force. If the mass of the object somehow becomes twice as much, its acceleration:
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HALVES
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A coconut and a feather fall from a tree through the air to the ground below. The amount of air-resistance force is:
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GREATER ON THE COCONUT
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